Abstract: An acoustic wave device includes a support substrate having a central region and a surrounding region located around the central region, a silicon oxide film that is located in the central region directly or indirectly and that has a side surface, a piezoelectric layer that is provided on the silicon oxide film and that has a first principal surface and a second principal surface, an excitation electrode provided on at least one of the first principal surface and the second principal surface, a cover film provided to cover the entire side surface of the silicon oxide film, a resin layer that is provided in the surrounding region and that is provided to cover the side surface of the silicon oxide film from above the cover film, and a wiring electrode that is electrically connected to the excitation electrode and that extends from the piezoelectric layer to the resin layer.

Abstract: An acoustic wave device includes a high-acoustic-velocity film, a low-acoustic-velocity film provided on the high-acoustic-velocity film, a piezoelectric layer provided on the low-acoustic-velocity film, and an IDT electrode provided on the piezoelectric layer. An acoustic velocity of bulk waves propagating through the high-acoustic-velocity film is higher than an acoustic velocity of acoustic waves propagating through the piezoelectric layer. An acoustic velocity of bulk waves propagating through the low-acoustic-velocity film is lower than an acoustic velocity of bulk waves propagating through the piezoelectric layer. The low-acoustic-velocity film includes a material including hydrogen atoms.

Abstract: An acoustic wave device includes a high-acoustic-velocity film, a piezoelectric layer provided directly or indirectly on the high-acoustic-velocity film, an IDT electrode provided on the piezoelectric layer, and a dielectric film provided on the piezoelectric layer to cover the IDT electrode. An acoustic velocity of bulk waves propagating through the high-acoustic-velocity film is higher than an acoustic velocity of acoustic waves propagating through the piezoelectric layer. The dielectric film includes a material including hydrogen atoms.

Abstract: An acoustic wave device includes a silicon oxide film, a piezoelectric body made of lithium tantalate, and interdigital transducer electrodes stacked on a supporting substrate made of silicon, in which the values of the wave length-normalized film thickness and the Euler angle of the piezoelectric body made of lithium tantalate, the wave length-normalized film thickness of the silicon oxide film, the wave length-normalized film thickness of the interdigital transducer electrodes in terms of aluminum thickness, the propagation direction of the supporting substrate, and the wave length-normalized film thickness of the supporting substrate are set such that represented by Formula (1) for at least one of responses of first, second, and third higher-order modes is more than about ?2.4, and TSi>20.

Abstract: An acoustic wave device includes a support substrate, a silicon nitride film stacked on the support substrate, a silicon oxide film stacked on the silicon nitride film, a piezoelectric body stacked on the silicon oxide film and made of lithium tantalite, and an IDT electrode provided on one main surface of the piezoelectric body. For a wavelength normalized film thickness of the piezoelectric body, an Euler angle of the piezoelectric body, a wavelength normalized film thickness of the silicon nitride film, a wavelength normalized film thickness of the silicon oxide film, and a wavelength normalized film thickness of the IDT electrode, values are set so that at least one of a response intensity of a first higher order mode, corresponding to the response intensity of a second higher order mode, and of a response intensity of a third higher mode is greater than about ?2.4.

Abstract: A multiplexer includes N acoustic wave filters each including one end connected in common and having a different pass band, in which when the N acoustic wave filters are in order from a side of a lower frequency of the pass band, at least one n-th acoustic wave filter among the N acoustic wave filters excluding an acoustic wave filter having the highest frequency of the pass band includes one or more acoustic wave resonators including a support substrate, a silicon nitride film laminated on the support substrate, a silicon oxide film laminated on the silicon nitride film, a piezoelectric body laminated on the silicon oxide film, and an IDT electrode provided on the piezoelectric body. All acoustic wave filters having a pass band in a higher frequency than a frequency of a pass band of the n-th acoustic wave filter satisfy fhl_t(n)>fu(m) or fhl_t(n)<fl(m).

Abstract: An elastic wave device includes a lamination layer film including a piezoelectric thin film on a support substrate. The lamination layer film is not partially present in a region located in an outer side portion of a region where IDT electrodes are provided. A first insulation layer extends from at least a portion of a region where the lamination layer film is not present to an upper portion of the piezoelectric thin film. A wiring electrode has a width of about 6 ?m and extends from the upper portion of the piezoelectric thin film to an upper portion of the first insulation layer, and extends onto a section of the first insulation layer in the region.

Abstract: An elastic wave device includes a lamination layer film including a piezoelectric thin film on a support substrate. The lamination layer film is not partially present in a region located in an outer side portion of a region where IDT electrodes are provided. A first insulation layer extends from at least a portion of a region where the lamination layer film is not present to an upper portion of the piezoelectric thin film. A wiring electrode extends from the upper portion of the piezoelectric thin film to an upper portion of the first insulation layer, and extends onto a section of the first insulation layer in the region.

Abstract: An acoustic wave device includes a silicon oxide film, a piezoelectric body made of lithium tantalate, and interdigital transducer electrodes stacked on a supporting substrate made of silicon, in which the values of the wave length-normalized film thickness and the Euler angle of the piezoelectric body made of lithium tantalate, the wave length-normalized film thickness of the silicon oxide film, the wave length-normalized film thickness of the interdigital transducer electrodes in terms of aluminum thickness, the propagation direction of the supporting substrate, and the wave length-normalized film thickness of the supporting substrate are set such that represented by Formula (1) for at least one of responses of first, second, and third higher-order modes is more than about ?2.4, and TSi>20.

Abstract: An acoustic wave device includes a material layer with Euler angles and an elastic constant at the Euler angles represented by Expression 1, a piezoelectric body including opposing first and second principal surfaces, is laminated directly or indirectly on the material layer and has Euler angles, and whose elastic constant at the Euler angles is represented by the Expression 1 below, and an IDT electrode on at least one of first and second principal surfaces of the piezoelectric body, and in which a wave length determined by an electrode finger pitch is ?.

Abstract: In a multiplexer, at least one acoustic wave filter includes a piezoelectric body made of lithium tantalate having Euler angles (?LT=0°±5°, ?LT, ?LT=0°±15°), a support substrate, and an interdigital transducer (IDT) electrode. A frequency fh1_t(n) of a first higher-order mode satisfies below Formulas (3) and (4) in all acoustic wave filters (m) having a higher pass band than at least one acoustic wave filter (n) (n<m?N) in at least one acoustic wave resonator among a plurality of acoustic wave resonators. fh1_t(n)>fu(m) Formula (3). fh1_t(n)<fl(m) Formula (4). Here, fu(m) and fl(m) represent the frequencies of the high-frequency end and the low-frequency end of the pass band in the m acoustic wave filters in Formulas (3) and (4).

Abstract: An acoustic wave device includes a material layer which has Euler angles and an elastic constant at the Euler angles, a piezoelectric body which includes first and second principal surfaces opposing each other, is laminated directly or indirectly on the material layer so that the second principal surface is on the material layer side and has Euler angles, and whose elastic constant at the Euler angles, and an IDT electrode which is disposed on at least one of the first principal surface and the second principal surface of the piezoelectric body. At least one elastic constant among elastic constants C11 to C66 of the material layer not equal to 0 and at least one elastic constant among elastic constants C11 to C66 of the piezoelectric body not equal to 0 have opposite signs to each other.

Abstract: An elastic wave device includes a supporting substrate, a high-acoustic-velocity film disposed on the supporting substrate, a low-acoustic-velocity film disposed on the high-acoustic-velocity film, a piezoelectric layer disposed on the low-acoustic-velocity film, and an interdigital transducer electrode disposed on the piezoelectric layer. The acoustic velocity of a bulk wave that propagates through the high-acoustic-velocity film is higher than the acoustic velocity of an elastic wave that propagates through the piezoelectric layer. The acoustic velocity of a bulk wave that propagates through the low-acoustic-velocity film is lower than the acoustic velocity of an elastic wave that propagates through the piezoelectric layer. The high-acoustic-velocity film is composed of SiNx, where x<about 0.67.

Abstract: A filter device includes a longitudinally coupled resonator elastic wave filter that includes IDT electrodes including low acoustic velocity regions in outer side portions of center regions of the IDT electrodes and high acoustic velocity regions in outer side portions of the low acoustic velocity regions in a direction orthogonal or substantially orthogonal to an elastic wave propagation direction, and defines and functions as a first bandpass filter, and elastic wave resonators that are electrically connected to the longitudinally coupled resonator elastic wave filter.

Abstract: An elastic wave device includes a multilayer film including a piezoelectric thin film laminated on a support substrate. In a region outside a region in which an IDT electrode is provided, the multilayer film is not disposed. A first insulating layer extends from at least a portion of the region to a region on the piezoelectric thin film. A wiring electrode extends to a region on the first insulating layer from a region on the piezoelectric thin film and to extend to a region on a portion of the first insulating layer located in the region. A support layer including a cavity defining a hollow space is provided on the support substrate. The support layer includes, on the wiring electrode, a portion extending from the region to a region above an inner end of the first insulating layer.

Abstract: An elastic wave device includes a SiNx layer stacked directly or indirectly on a supporting substrate made of a semiconductor material, a piezoelectric film stacked on directly or indirectly the SiNx layer, and an interdigital transducer electrode stacked directly or indirectly on at least one main surface of the piezoelectric film. In the SiNx layer, x is about 1.34 or more and about 1.66 or less.

Abstract: An elastic wave device includes a supporting substrate, a high-acoustic-velocity film disposed on the supporting substrate, a low-acoustic-velocity film disposed on the high-acoustic-velocity film, a piezoelectric layer disposed on the low-acoustic-velocity film, and an interdigital transducer electrode disposed on the piezoelectric layer. The acoustic velocity of a bulk wave that propagates through the high-acoustic-velocity film is higher than the acoustic velocity of an elastic wave that propagates through the piezoelectric layer. The acoustic velocity of a bulk wave that propagates through the low-acoustic-velocity film is lower than the acoustic velocity of an elastic wave that propagates through the piezoelectric layer. The high-acoustic-velocity film is composed of SiNx, where x< about 0.67.

Abstract: A multiplexer includes filters, a common terminal with which an inductance element is connected to a connection path of the common terminal and an antenna element and a capacitance element is connected in series to the connection path, and another inductance element. An input terminal of one of the filters is connected to the common terminal via the another inductance element, and is connected to a parallel resonator. In each of the filters other than the one filter, one of the input terminal and the output terminal, which is a terminal closer to the antenna element, is connected to the common terminal, and is connected to the series resonator.

Abstract: A multiplexer includes filters, a common terminal with which an inductance element is connected to a connection path of the common terminal and an antenna element and a capacitance element is connected in series to the connection path, and another inductance element. An input terminal of one of the filters is connected to the common terminal via the another inductance element, and is connected to a parallel resonator. In each of the filters other than the one filter, one of the input terminal and the output terminal, which is a terminal closer to the antenna element, is connected to the common terminal, and is connected to the series resonator.

Abstract: A multiplexer includes filters, a common terminal with which an inductance element is connected to a connection path of the common terminal and an antenna element and a capacitance element is connected in series to the connection path, and another inductance element. An input terminal of one of the filters is connected to the common terminal via the another inductance element, and is connected to a parallel resonator. In each of the filters other than the one filter, one of the input terminal and the output terminal, which is a terminal closer to the antenna element, is connected to the common terminal, and is connected to the series resonator.